Modifications:
UR Boost Pill
UR UICP
UR LICP
Evo X IC
UR SRI

About a week after my car was tuned, the car started throwing a p0105 (MAP circuit/Baro sensor) trouble code. Usually, this means that the vacuum lines are leaking or there is a leak in the system somewhere. The car was also getting crap for gas-mileage for a while too. I checked everything and found that the vacuum line containing the boost pill had wiggled itself down the nipple from the intake pipe and was loose. I re-tightened everything, and the code went away. This morning, the car threw a p0101 (the dreaded MAF voltage low code). I cleared it, and the code hasn't come back. However, the car is running much slower than normal. I checked the adapter and lines, and all of the wires appear to be attached correctly. I am getting a mass airflow reading when I plug into my ECU, as well. I really am at a loss. From what I am reading, it could be the filter wearing out the MAF. It could be the O2 sensor gone bad. It could be crap built up in my cat.

Does anyone have any thoughts on this one?

(In before you haz fail comments.)

 

Is it possible that oil from my cone filter is forming a residue on the MAF and causing a problem?

 

i get that when it rains... check and carefully clean your MAF and delete the code...

 

Try cleaning your MAF sensor with electrical contact cleaner .. then clear the code again

 

I cleaned the MAF and wires with the electrical parts cleaner. The code hasn't returned. This is annoying, as I sense that this is going to be a recurrent problem. Oh well. Thanks for the advice.

 

you could switch to a non-oiled filter.

 

If this happens often enough, I probably will.

 

boost leak test yet?

 

It has been tested. No leaks.

 

Same thing happened to me but the uic pipe came loose and was leaking. I went through and re clamped everything, erased the code and haven't had the code come up again. When did you do your leak down? I noticed that when the temperature went up locally is when the uic started leaking, I'm wondering if the warmer air had anything to do with my clamps loosening. They were the screw in type, I've since switched over to all t-clamps, much tighter!

 

Holy blast from the past!

So, I never did quite figure out what was the exact problem on my Ralliart, but I was having this problem with my GSR up until recently.

Here is what I have come up with as far as potential causes go:

1). Excessive fuel trimming WILL cause this problem. If your MAF is not dialed in, then you will more than likely throw this code or another related to the MAF. I have been going over my sensor calibrations over the past few weeks, and my trim are dead nuts on 0 (LTFT and STFT).

2). Some BPV's tend to throw this code. Unfortunately, the TiAL QR seems to be one of them. I have tried to work around this problem in my tune, and so far it appears to be working. However, this is a PITA to do. When in doubt, go Synapse.

3). Oiled air filters WILL cause this code to be thrown. The only filter that I have found to be truly oil free is of the AEM variety that they sell at local AutoZone's. K&N, aFe, Takada, etc. are never truly oil-free.

 

Cosworth filters are oil free!

 

Isn't that a panel filter? I am talking about commonly available conical filters.

 

Gotcha, yes it is, I misunderstood....